I could clinch you could clinch he could clinch we could clinch you could clinch they could clinch
V-ing form
I could be clinching you could be clinching he could be clinching we could be clinching you could be clinching they could be clinching
Perfect
I could have clinched you could have clinched he could have clinched we could have clinched you could have clinched they could have clinched
V-ing perfect
I could have been clinching you could have been clinching he could have been clinching we could have been clinching you could have been clinching they could have been clinching
Negation
Simple form
I could not clinch you could not clinch he could not clinch we could not clinch you could not clinch they could not clinch
V-ing form
I could not be clinching you could not be clinching he could not be clinching we could not be clinching you could not be clinching they could not be clinching
Perfect
I could not have clinched you could not have clinched he could not have clinched we could not have clinched you could not have clinched they could not have clinched
V-ing perfect
I could not have been clinching you could not have been clinching he could not have been clinching we could not have been clinching you could not have been clinching they could not have been clinching
Interrogative form
Simple form
could I clinch? could you clinch? could he clinch? could we clinch? could you clinch? could they clinch?
V-ing form
could I be clinching? could you be clinching? could he be clinching? could we be clinching? could you be clinching? could they be clinching?
Perfect
could I have clinched? could you have clinched? could he have clinched? could we have clinched? could you have clinched? could they have clinched?
V-ing perfect
could I have been clinching? could you have been clinching? could he have been clinching? could we have been clinching? could you have been clinching? could they have been clinching?
Interro-negative form
Simple form
could I not clinch? could you not clinch? could he not clinch? could we not clinch? could you not clinch? could they not clinch?
V-ing form
could I not be clinching? could you not be clinching? could he not be clinching? could we not be clinching? could you not be clinching? could they not be clinching?
Perfect
could I not have clinched? could you not have clinched? could he not have clinched? could we not have clinched? could you not have clinched? could they not have clinched?
V-ing perfect
could I not have been clinching? could you not have been clinching? could he not have been clinching? could we not have been clinching? could you not have been clinching? could they not have been clinching?